WO 03/016707 A1 discloses a fluid injector with a connector to a fuel supply, a housing, an actuator unit, and a valve body. The housing is double tubed and has a recess, which takes up the actuator unit. The actuator unit comprises a piezoelectric actuator, which acts on the needle. Between the walls of the double tube-shaped housing the fuel is led from the connector to a fuel inlet of the valve body. The valve body has a housing part with a recess, that takes up a needle. Depending on the position of the needle a nozzle is opened or closed and respectively fuel is injected or not.
Increasingly strict legislation concerning emissions of internal combustion engines, where a fluid injector may be arranged, make it necessary to put a lot of effort in measures that reduce the emissions. Very important for the prevention of exhaust emissions is, that the fluid can be dosed precisely.